Have you used Vue.js to build your one-page app or web interface? Have you also presently run a web performance assessment and are worried about the results? Are you searching for some practical ways to reduce loading times to offer the best-in-class user experience? If yes, then you have arrived at the right place!
Here, we will provide you with top-notch solutions that will help you optimise and speed up your Vue.js application. Before we talk about the steps, let’s first have a quick look at what Vue.js exactly is in the following section:
What is Vue.js?
Vue.js or Vue is an open-source and lightweight JavaScript framework that is most commonly employed for building reactive web user interfaces.
The main library of Vue is typically built around the ViewModel layer. Due to its two-way data binding functionality, it offers reactive synchronizations between the view layers and the model.
So, because of its functionality, it is possible to develop web apps on the SPA or single-page application model.
It works alongside CSS and HTML and offers a dynamic suite of tools designed to build the front end of web apps. In this case, the MVVM or model-view-viewmodel framework is most commonly used.
What is MVVM?
Model-view-viewmodel framework (MVVM) is typically an architectural or design pattern that is employed in the field of software development. More specifically, it is used in user interface or UI development. It works to separate the concerns of the user interface of an app from the underlying business logic and data.
What is the Key Benefit of Using Vue?
One of the significant advantages of Vue is that the data binding allows dynamic updating of HTML elements tied to underlying Vue objects. It means web apps can be quickly built and typically run in the user’s browser.
The best part is that refreshing the page is not required whenever the page is interacted with. It also incorporates responses to page events, especially within the JavaScript code.
What are the Best Ways to Optimise the Performance of Your Vue.js Apps?
Here are a few great ways in which you can optimise the performance of this outstanding framework:
Refrain from Unnecessarily Updating Elements
One of the common issues that Vue.js developers are most likely to come across is elements or a list of elements that are being unnecessarily rendered. It often results from a lack of understanding of the reactivity system of the framework.
Reactivity in Vue.js helps in converting plain JavaScript objects into reactive properties. Usually, you can update and render these objects more times than required.
Vue.js displays which specific elements are reactive and those that are not. It contributes to transforming the life of developers into an easier one. But, there may be many computed properties, reactive properties and properties assigned to a data object which can give rise to complications.
Whenever any new element is incorporated into a list of objects, there will be re-rendering of the entire list.
It is entirely unnecessary when you consider the date object. You may even find it not reactive, and it does not require updating for the unchanged elements.
An optimal method would be to reflect a new date which applies only to the changed elements. At the same time, the unchanged elements will remain as it is.
Solution
You can solve this problem by specifying the key property, which lets Vue recognise the elements effectively. So, reordering these can be done accordingly instead of cycling through and updating the overall list.
It is also required to create child components which help segment the app into smaller and more manageable components.
With this setup, only item components will be updated, especially in case the item encounters a reactive change. It can considerably enhance the performance of an app.
As a result, the list will be re-sorted depending on the fundamental properties. It ensures that there is re-rendering of only the needed elements.
Prevent Duplicate Rendering
Another important thing you must do involves rendering bulky elements or full lists multiple times.
For instance, a component may possess an entity property in the data object and the rendering of every entity is done by a child component if you have successfully followed the above-discussed solution.
You will find that the output of this entity property will be assigned a user token. Whenever you refresh this user token, there will be an update of the whole view even if the user.status remains unaffected, which is not ideal in terms of performance.
Solution
One of the best ways to address this problem is to pass the user. status value as a user.status prop, especially from the parent node. This way, Vue will prevent rendering it again if the value remains unchanged.
Certain dependencies like data values, props, and computed values can lead to re-rendering the overall list. So, finding any properties that could result in duplicate re-rendering is imperative.
You can also download the official Vue.js dev toolkit to solve this issue.
- After you download it, consider navigating to the ‘performance’ tab.
- Then, tap the start option to perform a performance check during the app load.
- Once you finish the checking part, visit the ‘Component Render’ tab.
- After that, you need to check that the number of components rendered associates with the number of events created.
Possessing more updated events than the created ones when there has been no modification in any values indicates taking the place of the duplicate rendering.
It can occur for multiple reasons, but as a best practice, you should refrain from altering entities more times than required.
Utilise Virtual Scrolling
Most contemporary websites, like social media platforms, now support infinite scrolling. The best part is that it does not affect the page speed.
But, within Vue, it requires the rendering of an extensive list. It considerably slows down the page as the user scrolls further down.
Solution
You need to implement virtual scrolling in Vue without impacting the page speed. Virtual scrolling allows the grid component of the page to reveal thousands of records on a single page. It is the suggested alternative to paging.
One of the vital things to note is that Vue-virtual-scroll-list is open-source. Also, the virtual scrolling project can render huge lists within Vue.
Compared to the others, it is known to be effortless. You again do not have to rely on absolute position, which could ‘break’ the user interface.
Optimized Event Handling
Each of the events within an app is different and so requires to be optimized accordingly. Due to this reason, utilizing a one-size-fits-all does not apply in this case. It could result in slow page times.
Two of the best examples of different events include @mouseover and window. scroll. It can be actioned multiple times in a single session by the user.
If the event handlers employed by these events are not optimized well, it may lead to long-winded calculations. It again could be run manifold times/second, which may result in lag.
Solution
Utilizing the debounce function is the most efficient way of optimizing event handling. It restricts the number of times events are being processed. So, it is possible to prevent unnecessary API calls and CPU cycles by limiting time-consuming events.
Replace or Remove Slow Components
Whether you are building components from scratch or importing 3rd party components into Vue, it is vital to ensure that their performance levels match up to the rest of the app.
Note that any single component displaying slow speeds can also considerably impact the entire product and lead to a poor user experience.
Solution
In this situation, the Vue.js dev toolkit comes to the rescue. You will observe an estimate of the rendering times for each component within the app, especially in the ‘performance’ tab.
It lets you effortlessly cross-check any of the components that are newly added with the existing components. Ultimately, you can check whether they are performing at the desired level.
If you find that the new component is taking longer to render when compared to the other components and it is almost impossible to reduce its usage, then one of the best ways is to remove it. You can even decide to replace it with an alternative option.
Render Page Sections Only Once
Whenever any particular element has been mounted, it only needs to be rendered once, as it is unlikely to change or need updating.
You could save time whenever the events occur, or the page is loaded by ensuring these elements are mounted only once.
Solution
You can use the v-once directive if a section in the application possesses data that is not likely to change throughout the entire page session. With this, you can ensure that this section is rendered only once.
This simple Vue directive evades any unnecessary rendering of an element. Small hacks like this facilitate the growth of the popularity of the framework.
Final Words
So, even if you are a developer, new to Vue.js, and are still in the learning stage, all the above-discussed tips will help you to improve the performance of your Vue.js applications.
If you find any problems in implementing these steps, one of the best things you can do is get in touch with a reputed Vue.js app development company. Make sure you choose one with a lot of experience in this field. By ensuring this, you would be able to achieve the best results.
